These data depict the elevations at the time of the survey and are only accurate for
that time. Users should be aware that
temporal changes may have occurred since this data set was collected and some parts
of this data may no longer represent actual surface
conditions. Users should not use this data for critical applications without a full
awareness of its limitations. Any conclusions drawn
from analysis of this information are not the responsibility of NOAA or any of its
partners. These data are NOT to be used for navigational purposes.

LIDAR data was collected using Merrick's ALS50 Phase 2 sensor. The raw data was verified
in MARS software for complete coverage of the project area, and bore sighted to align
the flight lines. Raw data files were parsed into manageable client-specific tiles.
These tiles were then processed through automated filtering that separates the data
into different classification groups: error points, ground points, and canopy/building
points. The data was next taken into a graphic environment to reclassify the erroneous
points that may remain in the LIDAR point cloud after auto filter.

1

2011-04-01T00:00:00

The NOAA Coastal Services Center (CSC) received the lidar files in las format. The
files contained lidar intensity and elevation measurements. CSC performed the following
processing for data storage and Digital Coast provisioning purposes: 1. Data converted
from UTM coordinates to geographic coordinates. 2. Data converted from NAVD88 heights
to ellipsoid heights using GEOID03. 3. The LAS data were sorted by latitude and the
headers were updated.

1

2011-06-30T00:00:00

The NOAA National Geophysical Data Center (NGDC) received lidar data files via ftp
transfer from the NOAA Coastal Services Center. The data are
currently being served via NOAA CSC Digital Coast at http://www.csc.noaa.gov/digitalcoast/.
The data can be used to re-populate the system. The data are archived in LAS
or LAZ format. The LAS format is an industry standard for LiDAR data developed by
the American Society of Photogrammetry and Remote Sensing (ASPRS); LAZ is a loseless
compressed version of LAS developed by Martin Isenburg (http://www.laszip.org/). The
data are exclusively in geographic coordinates (either NAD83 or ITRF94). The data
are referenced vertically to the ellipsoid (either GRS80 or ITRF94), allowing for
the ability to apply the most up to date geoid model when transforming to orthometric
heights.